<html>
<head>
	<title>PARENT</title>
	<script>
		function closeWindow() {
			parent.dhxWins.window("w1").close();
		}
	</script>
</head>
<body>
	<div style="margin: 10px;">
		<input type="button" value="close window" onclick="closeWindow();">
	</div>
</body>
</html>